Re: Serial Jumping

Bill Moran wrote:
> db.subscriptions@shepherdhill.biz wrote:
>> Hi,
>>
>> I have a table with BIG SERIAL field as Primary KEY. During high load,
>> entries in the BIG SERIAL field are jumped. One could see a row with
>> 1367 and expecting the next INSERT to be 1368, one would end up
>> getting 1369.
>>
>> Please is this normal?
>
> If transactions rollback, the serial value assigned during the rolled
> back transaction is skipped.  This has been discussed many times, it's
> a tradeoff between losing some #s now and again and taking a huge
> performance and code complexity hit to avoid it.
>
> If you absolutely need consecutive #s, then serial is not for you and
> you should implement your own method of acquiring sequential numbers.

You should also understand the several LARGE downsides to doing so. See
repeated past mailing list discussion.

--
Craig Ringer